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- configuration rom
- p1212 takes care of this, though it might be useful to compile the info into
a direct usable form (a struct)
- access control
- target login_descriptors : context of a login
- lun
- login_owner_id
- login_owner_EUI_64
- status_fifo_addr
- exclusive_flag
- fetch_agent_csr
- login_id
- reconnect_hold
- login procedure
- 8-byte (login_request_addr) block-write transaction to the
management_agent_csr
- target reads the initiator's EUI64 with 2 quadlet-read transactions
- target reads the login_request_orb at login_request_addr
- if initiator's EUI64 exists in login_owner_EUI_64 : access denied
- if initiator wants exclusive and lun already used : access denied
- if exclusive_flag set on lun's login_descriptor : access denied
- if no login_descriptor is available : resources unavailable
- if it's ok, target return a valid login_response
- reconnection procedure
- 8-byte (reconnect_request_addr) block-write transaction to the
management_agent_csr
- target reads the initiator's EUI64 with 2 quadlet-read transactions
- target reads the reconnect_request_orb at reconnect_request_addr
- a completion status is sent back to the initiator
- logout procedure
- 8-byte (logout_request_addr) block-write transaction to the
management_agent_csr
- a completion status is sent back to the initiator
- command execution
- requests and request-lists
- fetch agent initialization
- initiator allocates a dummy_orb, with a null pointer as next_orb,
of at least the minimum orb size
- initiator resets target fetch agent with a quadlet-write to
AGENT_RESET register
- initiator writes dummy_orb_addr with 8-byte block-write to
ORB_POINTER register
- fetch agent transition to ACTIVE state
- fetch agent reads the terminating dummy_orb and transition to
SUSPENDED state
- dynamic appends to request lists
- initiator constructs a linked-list of orbs in system memory, the
last orb's next_orb is null
- initiator updates the current last orb's next_orb to the first orb
of the linked-list
- initiator transmits a quadlet-write to the target's DOORBELL register
if the target is already in SUSPENDED state, the initiator may write
the first orb to ORB_POINTER register, and no DOORBELL is necessary
- data transfer
- completion status
- unsolicited status
- task management
- task sets
- basic task management model
- all tasks in a task set share the same execution characteristics :
reorderable/ordered
- reorderable/ordered feature is target dependent, see config_rom
- each task is identified by its orb's serial bus address
- all targets must at least implement the abort task, abort task set and
target reset management functions
- error conditions : entire task set is cleared on error condition
- fetch agent transitions to dead state
- target waits for sent status completion of all the completed tasks
- then target sends status completion for the faulty task, with dead bit
- task management requests
- abort task
- modify the rq_fmt to 3 in the task to be aborted's orb
- setup an ABORT_TASK management orb with the task orb's serial bus addr
- if target fetch an aborted task, sends REQUEST_COMPLETE on dummy_orb
- initiator may not reuse the memory of the task to abort until
completion has been received
- abort task set
- initiator sends an ABORT_TASK_SET management orb with login_id to target
- fetch agent transitions to dead state
- target waits for sent status completion of all the completed tasks
- then target sends status completion into the supplied status buffer
- initiator may not reuse the memory of any task in the task set until
a completion status is received for the abort task set management task
- logical unit reset (optional)
- initiator sends a LOGICAL_UNIT_RESET management orb with login_id to
target
- fetch agent transitions to dead state for all the lun's fetch agents
- target creates a logical unit attention condition to all the initiators
logged in to that lun (except the one initiating the reset)
- then target sends status completion into the supplied status buffer
- initiator may not reuse the memory of any task in the task set until
a completion status is received for the logical unit reset management
task
- target reset
- initiator sends a TARGET_RESET management orb with login_id to target
- fetch agent transitions to dead state for all the fetch agents
- target creates a logical unit attention condition to all the initiators
except the one initiating the reset
- then target sends status completion into the supplied status buffer
- initiator may not reuse the memory of any task in the task set until
a completion status is received for the target reset management task
- data structures
- ORB : rq_fmt_dep:128|notify:1|rq_fmt:2|rq_fmt_dep:29|rq_fmt_dep:nq
rq_fmt = 0|std, 1|rsvd, 2|vend, 3|nop
- Dummy ORB : next_ORB:64|ignore:64|notify:1|3:2|ignore:29|ignore:nq
- Command ORB : next_ORB:64|data_descr:64|notify:1|0:2|rsvd:1|direction:1|
speed:3|max_payload:4|page_table_present:1|page_size:3|
data_size:16|command_block:nq
speed = 0|S100, 1|S200, 2|S400, 3|S800, 4|S1600, 5|S3200
max payload = 2 ^ (max_payload + 2)
page size = 2 ^ (page_size + 8), if page_size != 0
(page_table_present):(page_size == 0)?unrestricted:normalized
(page_table_present):data_size = # of table elements
?data_size = data_descriptor size
- Management ORB : func_dep:128|notify:1|0:2|rsvd:9|function:4|func_dep:16|
func_dep:32|status_fifo:64
function = 0|LOGIN, 1|QUERY_LOGINS, 3|RECONNECT, 4|SET_PASSWORD,
7|LOGOUT, B|ABORT_TASK, C|ABORT_TASK_SET,
E|LOGICAL_UNIT_RESET, F|TARGET_RESET
- Access ORB
- LOGIN ORB : password:64|login_response:64|notify:1|0:2|exclusive:1|
rsvd:4|reconnect:4|0:4|lun:16|password_length:16|
login_response_length:16|status_fifo:64
login_response_length >= 12
reconnect timeout = 2 ^ reconnect
- login response : length:16|login_ID:16|command_block_agent:64|
rsvd:16|reconnect_hold:16
reconnect_hold <= 2 ^ reconnect - 1
- QUERY_LOGINS ORB : rsvd:64|query_response:64|n0..1:16|lun:16|rsvd:16|
query_response_length:16|status_fifo:64
- query response : length:16|max_logins:16|
(node_ID:16|login_ID:16|initiator_EUI_64:64)*n
- RECONNECT ORB : rsvd:128|n0..3:16|login_ID:16|rsvd:32|status_fifo:64
- LOGOUT ORB : rsvd:128|n0..7:16|login_ID:16|rsvd:32|status_fifo:64
- Task Management ORB : ORB_offset:064|rsvd:64|n0..fn:16|login_ID:16|
rsvd:32|status_fifo:64
fn = B|ABORT_TASK, C|ABORT_TASK_SET,
E|LOGICAL_UNIT_RESET, F|TARGET_RESET
if ABORT_TASK, ORB_offset is relevant
- page tables
- unrestricted page table : segment_length:16|segment_base:48
- normalized page table : segment_length:16|segment_base..segment_offset:48
- status block : src:2|resp:2|dead:1|len:3|sbp_status:8|ORB_offset:48|cmd_dep
- address pointer : node_ID:16|offset:46|rsvd:2
- ORB pointer : null:1|rsvd:15|offset:46|rsvd:2
- CSR
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